U.S. Surgeon General Jerome Adams has issued an advisory warning on the health risks of cannabis use among adolescents and pregnant women.

It is the first time a surgeon general has delivered an official advisory on marijuana since the 1980s. The number of states that permit recreational and medical cannabis use continues to rise and Adams warned that this has normalized it among adolescents.

“Over and over again I hear a great and rising concern about the rapid normalization of marijuana use and the impact that a false perception of its safety is having on our young people and on pregnant women,” he said.

The advisory warned that adolescents age 12-17 that report frequent use of marijuana showed a 130% greater likelihood of misusing opioids, referencing a 2018 paper from the Substance Abuse and Mental Health Services Administration.

Adams pointed out that the current cannabis on sale across the U.S. is a lot stronger than the weed smoked in previous generations.

The THC concentration in commonly cultivated marijuana plants has increased three-fold between 1995 and 2014, according to his advisory. It warns that marijuana sold in dispensaries in some states have an average THC concentration between 17.7% and 23.2%. “This ain’t your mother’s marijuana,” said Adams.

Health Human Services Secretary Alex Azar said the federal government is poised to launch a public awareness campaign designed to warn Americans of the risks associated with cannabis use. President Trump is donating $100,00 of his salary to help fund the digital ad campaign, which is designed to raise awareness of Adams’ advisory.

Azar said that state law may have changed, but he told a press conference that neither federal law has changed nor has science.

Thirty-three states and the District of Columbia have legalized medical marijuana use, and 11 states have legalized it for recreational use, despite it being illegal at a federal level. A number of states have also decriminalized possession of cannabis for recreational purposes.